From 7de55b7d6f09a2865279d3c41c0fbdbfdb87486a Mon Sep 17 00:00:00 2001 From: Johannes Thumshirn Date: Thu, 25 Mar 2021 00:47:26 +0900 Subject: block: support zone append bvecs Christoph reported that we'll likely trigger the WARN_ON_ONCE() checking that we're not submitting a bvec with REQ_OP_ZONE_APPEND in bio_iov_iter_get_pages() some time ago using zoned btrfs, but I couldn't reproduce it back then. Now Naohiro was able to trigger the bug as well with xfstests generic/095 on a zoned btrfs. There is nothing that prevents bvec submissions via REQ_OP_ZONE_APPEND if the hardware's zone append limit is met. Reported-by: Naohiro Aota Reported-by: Christoph Hellwig Signed-off-by: Johannes Thumshirn Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/10bd414d9326c90cd69029077db63b363854eee5.1616600835.git.johannes.thumshirn@wdc.com Signed-off-by: Jens Axboe --- block/bio.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) (limited to 'block') diff --git a/block/bio.c b/block/bio.c index 26b7f721cda8..963d1d406b3a 100644 --- a/block/bio.c +++ b/block/bio.c @@ -949,7 +949,7 @@ void bio_release_pages(struct bio *bio, bool mark_dirty) } EXPORT_SYMBOL_GPL(bio_release_pages); -static int bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter) +static void __bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter) { WARN_ON_ONCE(bio->bi_max_vecs); @@ -959,11 +959,26 @@ static int bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter) bio->bi_iter.bi_size = iter->count; bio_set_flag(bio, BIO_NO_PAGE_REF); bio_set_flag(bio, BIO_CLONED); +} +static int bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter) +{ + __bio_iov_bvec_set(bio, iter); iov_iter_advance(iter, iter->count); return 0; } +static int bio_iov_bvec_set_append(struct bio *bio, struct iov_iter *iter) +{ + struct request_queue *q = bio->bi_bdev->bd_disk->queue; + struct iov_iter i = *iter; + + iov_iter_truncate(&i, queue_max_zone_append_sectors(q) << 9); + __bio_iov_bvec_set(bio, &i); + iov_iter_advance(iter, i.count); + return 0; +} + #define PAGE_PTRS_PER_BVEC (sizeof(struct bio_vec) / sizeof(struct page *)) /** @@ -1094,8 +1109,8 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) int ret = 0; if (iov_iter_is_bvec(iter)) { - if (WARN_ON_ONCE(bio_op(bio) == REQ_OP_ZONE_APPEND)) - return -EINVAL; + if (bio_op(bio) == REQ_OP_ZONE_APPEND) + return bio_iov_bvec_set_append(bio, iter); return bio_iov_bvec_set(bio, iter); } -- cgit v1.2.3-59-g8ed1b